Mycotoxins in aquafeeds : The impact on rainbow trout

Abstract

In the following decade, several experimental studies were carried out that recognised the sensitivity of rainbow 13 Climate changeGlobally, climate change is manifested especially through elevated average yearly temperatures, increased CO2 levels and extreme weather conditions (drought or flood). These manifestations are all expected to affect the growth patterns of fungi and therefore the production of mycotoxins (Medina et al., 2017). This realization has led to concerns about upcoming food and feed security, and led to predictive models estimating the impact of climate change on mycotoxin production in cereals, in Europe (Van der . By the year 2040, DON contamination in wheat is expected to increase mainly in North-Western Europe, in some regions increased levels may be up to 3-fold compared to the original concentrations (van der Fels-Klerx et al., 2012a). Within the next 100 years, in a scenario of a 2 °C elevated temperature, the risk of aflatoxin B1 (AFB1) contamination in corn will increase mainly in Southern regions of Europe such as Spain, Italy and the Balkans because of optimal growth conditions for Aspergillus flavus (Battilani et al., 2016). In general, as a consequence of climate change Europe may witness an extension of AFB1 distribution from tropical to previously considered temperate areas, and a similar extension of Fusarium graminearum from Southern to Central and Northern Europe (Moretti et al., 2019). For instance, in the Netherlands, the main strain of Fusarium fungi in wheat always had been F. culmorum, but after the year 2000, F. graminearum became more dominant (Waalwijk et al., 2003). In Luxembourg, a shift from F. graminearum to F. culmorum and vice versa has been reported, indicating plasticity of Fusarium strains (Beyer et al., 2014). Overall, although exact proliferations under field conditions remain unpredictable, these studies provide several different examples confirming that in times of climate change, Europe should expect an increased presence and distribution of fungi on cereals and other crops, and the associated risk of contaminations with mycotoxins. Globalization of the tradeThe globalization of trade is leading to encountering unpredictable mycotoxin patterns in imported agricultural commodities, including aquafeed (Binder et al., 2007). For the relatively cold and wet parts of Northern Europe, trade globalization increases the risk of mycotoxins, simply because aflatoxin B1 is produced by Aspergillus fungi which thrive in warm and dry climate areas. One such example for the agricultural sector occurred in the Netherlands in 2013 (Focker et al., 2021) when aflatoxin M1 was discovered in cow milk, linked to aflatoxin B1contaminated maize imported from Eastern Europe and included in the feed of the animals consumed. Although a similar clear example has not been reported for aquaculture, the aquafeed sector certainly is aware of increased risks (Gonçalves et al., 2020a). For example, in Europe, increased risks exist for soybean, with soybean meal as a typical example of an...